Study On Preparation And Conductivity Property Of Polyaniline And Its Composites

This study briefly introduces the structure, characteristic,domestic and foreign research status of polyniline and its composites. Polyaniline and its composites obtained by different preparation methods.Using effective modified method to improve the structure of polyaniline and its composites,to improve all aspects of its performance, Especially its Conductivity Property. This study use the lower conductivity polyaniline and p-toluenesulfonic acid as a dopant to proton acid doping processing,to get doped polyaniline.So increasing its conductivity; Prepared polyaniline and doped polyaniline in different preparation methods,and find the best preparation methods;Then with acidified cellulose as a complex prepared several polyaniline/acidification cellulose composites, both have the good mechanical property, easy to process and have conductivity property of polyaniline; For prevent the polyaniline agglomeration occurs during polymerization, and further enhance the conductivity of polyaniline/acidification cellulose composites, study explores introducting acrylic acid into reaction system,that is acidification cellulose grafted acrylic acid and aniline polymerized in this process, Prepared new composite materials:Polyaniline/acrylic acid/acidified cellulose composites. And study the structure, Crystalline and conductivity of polyaniline and its composites.This study tabletting the polyaniline and its composites with pressed powder pellet machine, then tested the conductivity of polyaniline and its composites by a typical four-point probe (RTS-8) technique, the compared the electrical conductivity of them. Texted the degree of crystallinity ofpolyaniline and its composites with X-ray diffraction(XRD), and to study the affect of it to the conductivity of the material; Study the structure of polyaniline and its composites with Fourier Transform Infrared Spectroscopy(FTIR),then study the reason why conductivity different.From the experimental results.1, It is very low to either solution polymerization or emulsion polymerization prepared by polyaniline conductivity, almost no conductive; However, p-toluenesulfonic acid as a doping agent was prepared by doped polyaniline, the conductivity has improved significantly, conductivity are nearly two orders of magnitude. Different polymerization method to prepare polyaniline and doped polyaniline, Its conductivity is somewhat different, relatively speaking, either eigenstates or doped, the conductivity of solution polymerization Preparation of polyaniline slightly higher than polyaniline Emulsion Polymerization.2, For polyaniline, polyaniline/ acidification cellulose composite was made by acidification cellulose, this polyaniline in the acidification of the cellulose surface polymerization reaction, do not react chemically with the acidification of cellulose, Reduced agglomeration of polyaniline own aggregation, conductive path is more smooth and better conductivity, Its conductivity for Preparation of polyaniline conductivity increased by about4.3times than the solution polymerization. The use of the grafting method,as acrylic acid graft copolymer, composited polyaniline and the acidification fiber,made polyaniline/acrylic/the acidification cellulose composites,the conductivity of solution polymerization did not improve, but reduced.3, For doped polyaniline, Acidified cellulose composite made of doped polyaniline/to acidification cellulose composited, Its molecular crystallinity decreased, have no new functional groups, polyaniline in the surface of the acidified cellulose composited, Order of the polyaniline molecular chain improved, greatly weakened the agglomeration of polyaniline itself polymerization, Increasing the conjugated system, so that the free electrons showing a better separation performance, However, cellulose added, make the Polyaniline the doping effect of variation.So that the composite materials showing poor conductivity, conductivity compared to the solution polymerization doped polyaniline.Then conductivity reduced by more than one order of magnitude.When using grafting method,with acrylic acid as graft copolymer, preparation of doped polyaniline/acrylic acid/acidified cellulose composites, its conductivity even lower, the conductivity is even worse.Therefore, to improve the electrical property of polyaniline, Can be doped by the dopant,by acidification cellulose compositePreparation of acidified cellulose/polyaniline composite materials, but the two can not be together. By solution polymerization can also improve the conductivity of polyaniline; However, by the method of graft, with acrylic acid as graft copolymer, preparation of polyaniline/acrylic acid/acidified cellulose and doped polyaniline/acrylic acid/acidified cellulose composites have low conductivity, almost non-conductive. So, grafting does not improve the conductivity of polyaniline.